Cryptology ePrint Archive: Report 2013/534

Efficient Unobservable Anonymous Reporting against Strong Adversaries

Nethanel Gelernter and Amir Herzberg

Abstract: We present DURP, a decentralized protocol for
unobservable, anonymous reporting to an untrusted destination,
with low latency and overhead. DURP provably ensures strong
anonymity properties, as required for some applications (and not
provided by existing systems and practical designs, e.g., Tor),
specifically:
Provable unobservability against global eavesdropper and
malicious participants.
Provable source anonymity against a malicious destination.
Probable-innocence against a malicious destination which is
also a global eavesdropper.
DURP design is a modular combination of two modules: a
queuing module, ensuring fixed rates for certain events, together
with an anonymization module, which can use either Onion-Routing (DURP^OR) or Crowds (DURP^Crowds). We present anal-ysis, backed by simulation results, of the network properties and
performance of DURP, and show it has reasonable overhead. We
also use the analysis results to create an optimized version of
DURP.